Method of foaming ski boots

ABSTRACT

A double-wall liner of flexible material is put on the foot of the wearer or a mandrel corresponding to the foot of the wearer, the outer wall of the liner having therein an injection opening for an uncured foaming material and one or more vent openings. The mandrel or wearer&#39;&#39;s foot, with the liner thereon, is then inserted into a ski boot having one or more openings corresponding to the openings in the outer wall of the liner. The liner is keyed in position in the boot. The boot is then laced or buckled. An uncured resinous material and a catalyst therefor are mixed together and immediately injected into the liner through the injection opening. The foaming gas generated by reaction of the catalyst and resin foams the resin to produce an elastomeric foam which expands to fill the area between the walls of the liner and causes the outer wall of the liner to conform substantially to the inner surface of the boot and the inner wall of the liner to conform substantially to the mandrel or foot of the wearer. The foamed material is allowed to cure adequately in the liner before removal of the foot or mandrel from the liner. Stitching is provided along the instep of the liner to prevent the elastomeric foam from entering that portion of the liner, allowing that portion of the liner to expand laterally, and allowing the foaming gas to vent through the stitching into the atmosphere.

United States Patent 191 McAusland et al.

[451 Sept. 10, 1974 METHOD OF FOAMING SKI BOOTS [75] Inventors: RobertR. McAusland, Seattle; John M. Powell, Federal Way, both of Wash.

[73] Assignee: Anderson & Thompson Ski Co.,

Inc., Seattle, Wash.

221 Filed: Mar. 16,1970

21 Appl. No.: 19,914

Primary Examiner-Patrick D. Lawson Attorney, Agent, or Firm-Seed, Berry,Vernon & Baynham [57] ABSTRACT A double-wall liner of flexible materialis put on the foot of the wearer or a mandrel corresponding to the footof the wearer, the outer wall of the liner having therein an injectionopening for an uncured foaming material and one or more vent openings.The mandrel or wearers foot, with the liner thereon, is then insertedinto a ski boot having one or more openings corresponding to theopenings in the outer wall of the liner. The liner is keyed in positionin the boot. The boot is then laced or buckled. An uncured resinousmaterial and a catalyst therefor are mixed together and immediatelyinjected into the liner through the injection opening. The foaming gasgenerated by reaction of the catalyst and resin foams the resin toproduce an elastomeric foam which expands to fill the area between thewalls of the liner and causes the outer wall of the liner to conformsubstantially to the inner surface of the boot and the inner wall of theliner to conform substantially to the mandrel or foot of the wearer. Thefoamed material is allowed to cure adequately in the liner beforeremoval of the foot or mandrel from the liner. Stitching is providedalong the instep of the liner to prevent the elastomeric foam fromentering that portion of the liner, allowing that portion of the linerto expand laterally, and allowing the foaming gas to vent through thestitching into the atmosphere.

7 Claims, 6 Drawing Figures PAIENIEU 01914 3. 8'34. 044

SHEET 1 Bf 3 JOHN M. POWELL ROBERT R. MC AUSLAND INVENTORS.

ATTORNEYS 1 mammww m f JOHN. M. P E'LL' ROBERT R. A-USLAND v INVENTORS.

ATTORNIEYS PAIENIEu SEP 1 0:914

' sum 3 or 3 FIG, 25

FIG. 6

JOHN M.

INVENTORSI POWELL ROBERT R. MO AUSLAND Rmae ATTORNEYS BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates to a methodof fitting a boot to the foot of the wearer and the fitted boot per se.

2. Prior Art Relating to the Disclosure Ski boots are primarily designedto provide ankle support for the ankle of the wearer in addition towarmth and protection. For ski boots it is highly desirable to havefitted boots which will translate movements of the wearer directly tothe skis without dissipation due to movement of the feet in the boots.Boots, if not fitted correctly, compress the foot of the wearer atcertain pressure points and are too loosely fitted at other points. Theuneven pressure can be very painful to the wearer of the boot. With manyof the ski boots today being fabricated of a heavy gauge rigid plastic,correct fitting of the boots is necessary as the rigid plastic outerboot will not, in time, conform to the foot of the wearer. It isdifficult to pad individual ski boots because of the difference in sizeand shape of individual feet.

Custom fitting of ski boots and other athletic boots by casting of afoaming material around the foot in situ is known. Generally, a singlewall liner is put around the foot of the wearer. An uncured foamingresin is then put in the boot. The wearer then inserts his foot with theliner thereon into the boot and the boot is laced or buckled to thedesired tightness. The foam expands to fill the areas between the linerand the inner surfaces of the boot. Difficulties have been experiencedwith the previously described process because of precure of the foammaterial. The top of the boot presents a generally unfinished appearanceunless the exposed foamed area is covered. If not covered water frommelting snow crusted on the boots during skiing soaks into theelastomeric foam. Thereafter it is difficult to completely remove thewater from the foamed area.

Other techniques of custom fitting boots are disclosed in US. Pat. Nos.3,325,919, 3,325,920, 3,329,953 and 3,377,721.

SUMMARY OF THE INVENTION Ski boots and other athletic type boots arefitted to the foot of the wearer utilizing a double-wall liner having aninner wall approximating the wearers foot, the.

liner adapted to fit into an outer ski boot shell. Corresponding accessopenings are provided in the boot and the outer wall of the double-wallliner to allow an elastomeric material to be injected between the wallsof the double-wall liner. The liner is keyed in position in the outerboot. The wearer puts the double-wall liner on a mandrel correspondingto his foot or his foot, and steps in the boot, or the wearer may stepinto the boot with the liner previously installed. An uncured resin,catalyst and foaming agent are mixed together and injected through theinjection opening in the liner. The uncured foam expands after injectioninto the liner and conforms the outer wall of the liner substantially tothe contour of the inner surface of the outer boot and conforms theinner wall of the liner to the outer surface of the foot of the wearer.After allowing the resin to cure with the foot in the liner and theliner in the boot the liner may be removed from the boot and the foot.The liner is provided with means allowing the foaming gas to vent andallowing it to stretch laterally. Such means may include stitchingrunning the length of the liner,

the stitching preventing the foaming material from entering that portionof the liner. The liner is made of a pliable, elastomeric material.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective viewof the liner and boot of this invention;

FIG. 2 is a perspective view of the liner in the outer boot with amandrel or the wearers foot positioned in the boot, foaming resin beinginjected into the space between the walls of the double-wall linerthrough the tube connected to the container;

FIG. 3 is a cross sectional view along section line 3-3 of FIG. 2;

FIG. 4 is a cross sectional view along section line 44 of FIG. 1.

FIG. 5 is a cross sectional view of the boot with the foamed liner inposition, the liner keyed in position; and

FIG. 6 is a partial view of one means of plugging the injection and ventopenings in the outer boot after the boot has been fitted to the foot ofthe wearer.

DETAILED DESCRIPTION OF THE INVENTION 4 Fitting of ski boots by themethod of this invention can be done with existing boots of leather orsynthetic material or with new boots. If an existing boot is used thepadding in the boot is generally removed to provide ample room in theboot for the foaming material to expand the walls of the liner againstthe inner surface of the boot and the outer surface of the foot of thewearer.

Referring to FIGS. 1 and 4 the double-wall liner 10 includes an innerwall 10a and an outer wall 10b fabricated into a toe section 12 a footsection 14 and a leg section 16. A flexible sole 11 may be provided ifdesired. A slit 18 runs from the top of the liner downwardly towards thetoe section allowing a mandrel corresponding to the foot of the weareror the foot of the wearer to be easily inserted and removed from theliner. The liner is provided with speed laces 20, a zipper or flap sothat the liner can be closed about the mandrel or foot of the wearer.The outer wall of the liner is provided with one or more openings 22 and24 for injection of an uncured foaming resin into the space between thewalls of the liner and venting of air and the foaming gas from thespace. The uncured foaming resin may be injected into the space near theheel of the liner as shown in FIG. 1. A vent opening or openings 24 maybe placed at any suitable location such as in the toe portion or, asshown, near the ankle. The liner is fabricated from a flexible materialsuch as neoprene, leather, vinyl plastic, etc. Both walls of the linermay be of the same or of different material. Preferably the inner wallis fabricated from lined neoprene with the outer wall made fromrelatively thin vinyl or leather. As shown in FIGS. 1 and 4 parallelseams 26 and 28 extend parallel to slit l8. Seam 30 extends around thetoe portion of the liner. These seams permit gas generated as a resultof the reaction between the catalyst and resin to be vented through theseams to the atmosphere. Very small amounts of the uncured foaming resinare able to penetrate into the stitched areas as shown in FIG. 4. It isdesirable to leave the toe portion of the liner unfoamed so that thetoes of the wearer have ample room for movement in the boot. It is alsodesirable that no foam enter the space between the seams 26 and 28 andslit 18 of the liner, thus providing space 32 of the liner which can beexpanded laterally by the foot of the wearer.

Bosses 34 and 36 of rubber or other suitable material are secured toopenings 22 and 24 by adhesive or other means. Bosses 34 and 36 includea shoulder portion 35 of substantially the same diameter as openings 21and 23 in the outer boot. The shoulder portions key the liner inposition in the boot and aid in preventing upward movement of the heelportion of the liner in the boot during use. The inlet openings of thebosses should be long enough to extend through corresponding openings 21and 23 in the outer boot.

Ankle padding 44 may be included as an integral portion of liner asshown in FIG. 1 or the padding 43 may be stitched around the top of theouter boot as shown in FIG. 5. The padding secured to the boot as shownin FIG. 5 serves a second function, that of preventing the heel of theliner from moving or working upwardly during use of the boots by thewearer.

The outer boot 38 is a conventional ski boot. Although the boot shown isclosed by buckles, lace boots may also be used. The outer boot hasopenings 21 and 23 therein positioned relative to the openings 22 and 24in the outer wall of the liner.

METHOD OF FITTING In practice a liner is fabricated so that the innerwall thereof approximates the foot of the wearer. A conventional sock ofwool, cotton or nylon, which is generally worn with any ski boot, isplaced on the foot of the wearer and worn during foam fitting of theliner to the foot and to the outer boot. The liner may be provided withlacing, zippers or other means for holding it on the foot. When theliner is inserted into the boot the shoulder portion 35 of bosses 34 and36 is keyed into position in openings 21 and 23 of the outer boot.

A tube 40 is attached to the inlet end of boss 34 extending throughopening 21 in boot 38, the opposite end of the tube having means thereonsecuring it to a container 42. Measured amounts of resin and catalystfor the resin are poured together in container 42, the container closed,and the components mixed by shaking, swirling or other suitable manner.The resin used is perferably of the type which reacts immediately andcures within minutes of the time the components are mixed together.Commerically available urethane or silicone foams are typical of theelastomeric foams which may be used. The gaseous foaming agent generatedon mixing of the resin and catalyst generates pressure within thecontainer 42 which aids in forcing the uncured, foaming resin throughtube 40 into the space between the inner and outer walls of thedouble-wall liner 10. As the foaming material enters between the wallsof the liner it continues to expand and fills the interstices thereinwith the result that the outer wall of the liner conforms substantiallyto the inner surface of the outer boot and the inner wall of the linerconforms substantially to the mandrel or foot of the wearer. Excess gasin the liner is vented through the stitched seams 26 and 28 and to theatmosphere and through vent opening 24. If needed, additional ventopenings may be provided. By providing vent passages the generated gasis not entrapped in the liner with resulting formation of voids.

As soon as all of the foaming material is injected into the boot 38,tube 40 is removed from boss 36 and the foam allowed to cure with themandrel or foot of the wearer in the boot. Generally the foams used aresubstantially cured in a matter of minutes. The boot is then unbuckledand the mandrel or foot removed. The liner may be removed if desired. Itis recommended that the foam in the liner be allowed to fully cure for aperiod of 12 or more hours before actual use of the liner. There isusually a small amount of shrinkage in the liner due to shrinkage offoam in the boot. It is desirable to provide an unfoamed space 32 whichallows the liner to stretch laterally upon re-insertion of the foot ofthe wearer into the liner. The ends of bosses 34 and 36 protruding fromthe outer wall of the liner are cut flush with the outer surface of theboot 38 after the foam has been injected. The openings 21 and 23 in theouter boot are then plugged with plug 39 as shown in FIG. 6 or othersuitable means.

The liner may be provided, if desired, with a semirigid sole 11 on thebottom thereof. In addition, the top of the liner may be provided withconventional padding 44 for the ankle of the wearer, or the outer bootmay be provided with the necessary padding.

The method of this invention allows measured amounts of resin andcatalyst to be mixed together so that waste of the foaming materials isavoided. By venting the gas generated during foaming through stitchedareas of the liner, voids in the foamed material are not formed. Thepressure generated by the gas during foaming in the container acts todrive the foaming material into the space between the walls of theliner, the foam further expanding in the area between the walls of theliner to fill every available space with foam.

The embodiment of the invention in which an exclusive property orprivilege is claimed or defined as follows:

l. A method of custom fitting a boot to a mandrel corresponding to thefoot of the wearer or to the foot of the wearer comprising:

providing an outer boot shell made of a substantially rigid materialwith an injection opening therethrough,

providing a flexible, double-wall liner for the boot shell, the innerwall of which approximates the surface of the mandrel or foot of thewearer and the outer wall of which has an injection inlet adapted toregister with the injection opening in the boot shell,

inserting a mandrel or foot of the wearer in the liner,

inserting the liner into the boot shell with the injection inletregistering with the injection opening, closing the boot shell aroundthe liner, mixing an uncured foamable liquid resinous material andcatalyst in a flexible closed container having an outlet tube, the resinand catalyst reacting to generate a foaming gas, connecting the outlettube with the injection inlet of the liner in a closed system, thefoaming gas generated by mixing of the resin and catalyst aiding toforce the uncured foaming resin into the space between the walls of theliner. 2. The method of claim 1 wherein the injection opening forinjection of the foaming resin is located near the heel of the boot andliner.

3. The method of claim 1 wherein the liner includes a vent openinghaving an outwardly protruding gas outlet secured thereto, the boothaving a corresponding opening adapted to receive the outwardlyprotruding outlet.

4. A boot fitted to the foot of the wearer comprising,

an outer boot of substantially rigid material having a sole and an upperand at least two plugged openings in the upper, including an injectionopening and a vent opening,

a flexible, double-wall liner having a toe section, foot section and legsection,

a closeable slit running from the upper edge of the liner downwardly ofthe instep towards the toe section of the liner, allowing the foot to beinserted and removed from the liner,

openings in the outer boot of the liner corresponding to the injectionand vent openings in the outer boot for entry of an uncured foam intothe space between the walls of the double-wall liner and vent of foaminggas from the space between the walls of the double-wall liner,

6 fittings secured around each of the openings in the outer wall of theliner having shoulder portions thereon adapted to key into thecorresponding openings in the outer boot aiding and preventing upwardmovement of the heel portion of the liner in the boot during use, and

a cured elastomeric foam between the walls of the liner which conformthe inner wall of the liner substantially to the foot of the wearer andthe outer wall of the liner substantially to the inner surface of theouter boot.

5. The boot of claim 4 wherein the liner includes stitched seams runningsubstantially parallelto the slit, the seams allowing foaming gas tovent therethrough, thereby preventing formation of voids.

6. The boot of claim 4 wherein the outer boot includes a padded portionsecured around the top of the leg section thereof, the padded sectionaiding and preventing upward movement of the double-wall liner in theboot.

7. The boot of claim 4 wherein the double-wall liner is removable fromthe outer boot.

1. A method of custom fitting a boot to a mandrel corresponding to the foot of the wearer or to the foot of the wearer comprising: providing an outer boot shell made of a substantially rigid material with an injection opening therethrough, providing a flexible, double-wall liner for the boot shell, the inner wall of which approximates the surface of the mandrel or foot of the wearer and the outer wall of which has an injection inlet adapted to register with the injection opening in the boot shell, inserting a mandrel or foot of the wearer in the liner, inserting the liner into the boot shell with the injection inlet registering with the injection opening, closing the boot shell around the liner, mixing an uncured foamable liquid resinous material and catalyst in a flexible closed container having an outlet tube, the resin and catalyst reacting to generate a foaming gas, connecting the outlet tube with the injection inlet of the liner in a closed system, the foaming gas generated by mixing of the resin and catalyst aiding to force the uncured foaming resin into the space between the walls of the liner.
 2. The method of claim 1 wherein the injection opening for injection of the foaming resin is located near the heel of the boot and liner.
 3. The method of claim 1 wherein the liner includes a vent opening having an outwardly protruding gas outlet secured thereto, the boot having a corresponding opening adapted to receive the outwardly protruding outlet.
 4. A boot fitted to the foot of the wearer comprising, an outer boot of substantially rigid material having a sole and an upper and at least two plugged openings in the upper, including an injection opening and a vent opening, a flexible, double-wall liner having a toe section, foot section and leg section, a closeable slit running from the upper edge of the liner downwardly of the instep towards the toe section of the liner, allowing the foot to be inserted and removed from the liner, openings iN the outer boot of the liner corresponding to the injection and vent openings in the outer boot for entry of an uncured foam into the space between the walls of the double-wall liner and vent of foaming gas from the space between the walls of the double-wall liner, fittings secured around each of the openings in the outer wall of the liner having shoulder portions thereon adapted to key into the corresponding openings in the outer boot aiding and preventing upward movement of the heel portion of the liner in the boot during use, and a cured elastomeric foam between the walls of the liner which conform the inner wall of the liner substantially to the foot of the wearer and the outer wall of the liner substantially to the inner surface of the outer boot.
 5. The boot of claim 4 wherein the liner includes stitched seams running substantially parallel to the slit, the seams allowing foaming gas to vent therethrough, thereby preventing formation of voids.
 6. The boot of claim 4 wherein the outer boot includes a padded portion secured around the top of the leg section thereof, the padded section aiding and preventing upward movement of the double-wall liner in the boot.
 7. The boot of claim 4 wherein the double-wall liner is removable from the outer boot. 